Blindness is one of the most debilitating conditions that can severely impact people’s ability to lead independent lives.
Bionic Vision Australia is a national consortium of researchers working together to develop a bionic eye that can help restore sight to people with particular forms of vision impairment. The aim is to restore the sense of vision to people living with blindness and low vision. Initially, this technology targets patients with retinitis pigmentosa and age-related macular degeneration. With time and more research, it is possible in future that this technology can help patients with other vision impairment conditions.
The bionic vision system consists of a camera, attached to a pair of glasses, which transmits high-frequency radio signals to a microchip implanted into the retina. Electrodes on the implanted chip convert these signals into electrical impulses to stimulate cells in the retina that connect to the optic nerve. These impulses are then passed down along the optic nerve to the vision processing centres of the brain, where they are interpreted as an image.
To benefit from this technology, patients need to have a functional visual pathway from the retina to the brain along the optic nerve, as well as some intact retinal cells. As such, the two medical conditions that this technology aims to address are retinitis pigmentosa and age-related macular degeneration.
What does the patient see?
A person using a retinal implant to see won’t experience vision in the same way that a person with a healthy eye does. It will be quite basic to start with and they will need training to adapt to the implant. With time, training and patience, people will be able to use this visual information so they can be more independent and mobile.
The retinal implant bionic eye works by stimulating the perception of light in a patient. A phosphene is a perceived spot of light in the visual field. What our technology aims to do is stimulate many of these phosphenes across the visual field in a way that enables the patient to put together a picture of what they’re looking at.
The more electrodes an implant contains, the more phosphenes are capable of being generated and the more detail a patient may be able to see. The first wide-view prototype device has 98 electrodes. The second High-Acuity device has more than 1024 electrodes.